23.3 Saving the density matrix

DM,record.ifil;

The first-order density matrix in AO basis is stored in record record on file ifil.
Two types of density matrices are stored in the same record: the one without orbital relaxation contribution
is stored as set 1, meanwhile with the orbital relaxation contribution, it is stored as set 2. If
the NORELAX directive is given on the EXPEC card prior to the DM card, only the orbital unrelaxed density matrix
is computed and stored. See also NATORB in section 23.4.